here's what I have found from the manufacturor...

Most Insignia TVs can be controlled using various brands
of Universal Remote Controls (URC). To do this, the user
needs to enter the correct code number into the Universal
Remote. This code will be a different number for the
various URCs. The owner's manual for the URC typically
includes table and code listings for various TV brands
and may include Insignia TVs as well. Use the code listed
in the URC manual when available. For cases when the
code is not listed, use the following guideline:

Look in the URC manual for the following 6 brands of TVs.
For each, there will be one or more code numbers listed.
In most cases, one or more of these codes will work

with the Insignia TV. The brands to look for in URC owner's
manual are:

Sylvania, Zenith, Emerson, Memorex, Orion, Sansui

Some URCs, are also capable of "learning" new commands.
For these learning URCs, the user can "teach" the command
for each button of the Insignia TV to the URC by pointing
the two remotes at each other and pressing the corresponding
buttons. The exact procedure will depend on the specific
remote used. The URC's owner's manual should explain
the process.

also, I have COX and the URC for cox finally works for
me, heses what i did:

Press TV
Press and hold setup button until TV button blinks twice
Press 9-9-1
press TV
Press Power
Press Chanel Up repeatedly until set turns off
Press Setup to lock in code

this is what COX told me to do, i tried it 3 times to
no avail, I then tried it again a few minutes later, and
it worked, so give it a few tries if it dosent work right
away.